Leica

Leica Camera AG (historically Ernst Leitz Wetzlar) is the German manufacturer that invented the 35mm format and established the rangefinder system as we know it today. For the Leica M-mount community, this brand is the reference point against which all others, Zeiss, Voigtländer, Canon, and Konica, are measured.

Leica lenses are broadly categorized by their maximum aperture (Summicron, Summilux, etc.) rather than focal length. They are legendary for their high manufacturing standards, compact size, and a distinct optical evolution that splits into two main eras: the "Mandler Era" (classic, smooth rendering) and the "Karbe Era" (modern, clinical perfection).

History

Leica's history is the history of modern photography itself.

The Ur-Leica and the Screw Mount (1914 to 1953)

In 1914, Oskar Barnack, an engineer at Ernst Leitz Optische Werke, created the "Ur-Leica," the first still camera to use 35mm cinema film horizontally. This "small negative, large picture" concept revolutionized photography. The early commercially released cameras (Leica I, II, III) used the Leica Thread Mount (LTM/M39), setting the first global standard for interchangeable lenses [[1]].

The M-Mount Revolution (1954 to Present)

In 1954, Leica released the Leica M3, introducing the Leica M-Bayonet. This mount was faster to change than the screw mount and, crucially, allowed for a combined viewfinder/rangefinder with parallax corrected framelines.

• The Name Change: While the cameras were always named "Leica" (LEI-tz CA-mera), the company itself was named Ernst Leitz Wetzlar until 1986, when it officially changed its corporate name to Leica due to the strength of the brand [[1]].

Mandler vs. Karbe (The Two Souls of Leica)

For collectors, understanding the "Chief Optical Designer" eras is vital:

• The Mandler Era (1950s to 1980s): Led by Dr. Walter Mandler (often working from Leica Canada / ELCAN). His lenses (like the pre-ASPH Summilux 35mm and Noctilux f/1) prioritized smooth transitions and "glow" over clinical sharpness. They are prized for their "romantic" character [[2]].
• The Karbe Era (1990s to Present): Led by Peter Karbe. His philosophy (seen in the Summicron APO and Summilux ASPH lines) focuses on absolute resolving power, high micro contrast, and the elimination of aberrations. These lenses are technically perfect but occasionally criticized as "clinical" [[3]].

Product Lines (Lens Naming System)

Leica lenses are named according to their maximum aperture (speed), regardless of focal length [[4]].

Noctilux (f/1.25, f/0.95, f/1.0, f/1.2)

The "King of the Night."

• Role: Ultra high speed lenses designed for extreme low light and massive subject separation.
• Key Models: The Noctilux 50mm f/1 (Mandler design) is famous for its swirly bokeh. The modern Noctilux 50mm f/0.95 ASPH is a technical marvel of sharpness.

Summilux (f/1.4)

The professional standard.

• Role: The balance between speed and size.
• Key Models: The 35mm Summilux ASPH (FLE) is perhaps the most popular reportage lens in the world. The 50mm Summilux ASPH is often cited as the "perfect" standard lens.

Summicron (f/2)

The "Reference."

• Role: Prioritizing size, zero distortion, and resolution over raw speed.
• Key Models: The Summicron 35mm IV ("King of Bokeh") and the APO-Summicron 50mm (a $9,000 engineering benchmark) are the standouts.

Elmarit (f/2.8) & Summarit (f/2.4 or f/2.5)

The compact choice.

• Role: High contrast and sharpness in the smallest possible package.
• Key Models: The Elmarit 28mm ASPH is one of the sharpest wide angles ever made, yet tiny enough to block zero viewfinder space.

Technical Specifications

Feature	Specification Details
Native Mount	Leica M-Bayonet
Flange Distance	27.80mm
Focus Mechanism	Rangefinder coupled via a cam on the rear of the lens.
6-Bit Coding	Pre-2006: Uncoded (M8/M9/M10 users must select manually). Post-2006: 6 black/white paint pits on the flange allow digital bodies to identify the lens for EXIF and in camera corrections [[5]].
Aperture Blades	Typically 8 to 11 blades (straight or curved depending on era).
Filter Thread	Standardized mostly to E39 (39mm) and E46 (46mm), with larger lenses using E49, E55, or E60.

Why Photographers Choose Leica

• Value Retention: Unlike almost any other camera equipment, Leica lenses (especially brass versions) tend to appreciate in value over time.
• The "Mandler Glow": Photographers specifically hunt for Canadian made lenses (like the 35mm Summicron v4) to get a specific, non linear transition to out of focus areas that modern computer optimized lenses cannot replicate [[2]].
• Tactile Experience: The "Leica focus throw", silky smooth, perfectly damped, with a distinct click at aperture stops, is the haptic standard that other manufacturers (like Voigtländer) try to emulate but rarely equal.

---

Sources

• [1] Leica Camera AG (History): https://leica-camera.com/en-int/world-of-leica/history
• [2] The Leica Society (Mandler History): https://leicasocietyinternational.org/blog/2021/4/9/walter-mandler-legendary-lens-designer
• [3] Overgaard (Peter Karbe Interview): https://www.overgaard.dk/leica-lens-designer-peter-karbe.html
• [4] Ken Rockwell (Lens Names Explained): https://www.kenrockwell.com/leica/lens-names.htm
• [5] Summilux.net (Serial Numbers & Datings): http://www.summilux.net/numeros/index.php